The current invention relates to water processing. Water is an essential resource to every community. In many locations water may be scarce or expensive to purify for domestic use. Consequently, many efforts have been made to develop a more cost effective way to produce abundant sources of water.
U.S. Pat. No. 6,511,525 to Spletzer et al., which is herein incorporated by reference for all that it contains discloses a method and apparatus for extracting liquid water from moist air using minimal energy input. The method can be considered as four phases: (1) adsorbing water from air into a desiccant, (2) isolating the water-laden desiccant from the air source, (3) desorbing water as vapor from the desiccant into a chamber, and (4) isolating the desiccant from the chamber, and compressing the vapor in the chamber to form liquid condensate. The liquid condensate can be removed for use. Careful design of the dead volumes and pressure balances can minimize the energy required. The dried air can be exchanged for fresh moist air and the process repeated. An apparatus comprises a first chamber in fluid communication with a desiccant, and having ports to intake moist air and exhaust dried air. The apparatus also comprises a second chamber in fluid communication with the desiccant. The second chamber allows variable internal pressure, and has a port for removal of liquid condensate. Each chamber can be configured to be isolated or in communication with the desiccant. The first chamber can be configured to be isolated or in communication with a course of moist air. Various arrangements of valves, pistons, and chambers are described.
U.S. patent application Ser. No. 09/788,370 to Faqih, which is herein incorporated by reference for all that it contains discloses systems and methods for extraction of freshwater from ambient air in regions of extremely hot and humid climates, for supply of drinking water and freshwater for small to large groups of people in remote and isolated areas or wherever freshwater resources are not conveniently accessible. Compact mobile units are disclosed to provide freshwater and drinking water for resort areas, to passengers on land and sea vehicles, in situations of emergency, and to areas of water shortage. The art of adaptation of commercial dehumidification units is taught in design and construction of apparatus for production of freshwater and drinking water. Preparation of drinking water included ultraviolet disinfection, ozone treatment, and/or chlorine addition; activated carbon and ion exchange filters; and adding of fluorine, air/oxygen to refresh the water storage units, and minerals for taste and health provisions. For energy economy and use of independent electric power supply, the produced water may flow under gravitational forces entirely or with the assistance of small boasting pumps. Lukewarm, hot, cold, and/or cold carbonated drinking water are provided as well as freshwater for other usage.
U.S. Pat. No. 3,777,456 to Lund, which is herein incorporated by reference for all that it contains discloses that water is extracted from the atmosphere by circulating a large volume of a solution of lithium chloride in water continuously over a Munters packing in a tower of conventional cooling tower design. Excess solution formed as a result of the absorbtion of water is bled off and passed through a desalination plant where product water is produced. Concentrated brine is returned to the circulation volume.
U.S. Pat. No. 6,156,102 to Condrad et al., which is herein incorporated by reference for all that it contains discloses a process of separating water from ambient air involves a liquid desiccant to first withdraw water from air and treatment of the liquid desiccant to produce water and regenerated desiccant. Water lean air is released into the atmosphere. Heat generated in the process is recycled. The drying capacity, or volume of water produced, of the system for a given energy input is favored over the production of dried air.
U.S. patent application Ser. No. 11/198,771 to Eplee et al., which is herein incorporated by reference for all that it contains discloses a method and apparatus for extracting liquid water from ambient air, including ambient air in severely arid and hot climates. An example apparatus uses a sorption-desorption-condensation cycle using a sorption wheel to extract moisture from ambient air and concentrate the water vapor driven off from the sorption material in a circulating gas, with condensation of liquid water from the circulating gas.